The Adidas Ultraboost 21 shoe is known for its comfort, sleek style and energy return. Whether you're running, walking or training, these Adidas workout shoes are a staple for anyone with an active lifestyle. The sneakers have a sock-like fit, lace closure, knit upper and a cushiony sole. As the Adidas website puts it, the Ultraboost 21 is the "pinnacle harmonization of weight, cushioning, and responsiveness." It's a great gift too!